RMERF counts March 10

Saturday, March 10Mount Lorette [Day 9] 0715-1845 (Jim Davis, assisted by Ruth Morrow). The temperature at 0715 was -14C, the high was 7C at 1600 and it was 2C at the end of observation at 1845. Ground winds were generally very light and variable and calm for the first and last 2 hours of the day, with the exception of 1300-1700 when they were 2-10 gusting 15 km/h. Ridge winds were light to moderate W and skies were cloudless all day. A season-high total of 80 raptors of a season-high 6 species were counted between 0917 and 1740. Of these 28 were seen between 1600 and 1700 and another 28 between 1700 and 1740. The flight comprised a season-high 9 Bald Eagles (7a, 2sa), 2u Sharp-shinned Hawks (the first of the season), 3 adult Northern Goshawks (the first of the season), 2 light morph Rough-legged Hawks that migrated together, a season-high 63 Golden Eagles (43a, 4sa, 9j, 7u) and 1 dark morph Gyrfalcon that flew to the west late in the day. Only 3 birds, including the 2 Rough-legged Hawks, were seen on the western route; the rest used the eastern ridges with about 70% of the birds after 1600 originating from the Wasootch Creek area north of the northern end of the Fisher Range and gliding to Mount Lorette where they soared high before continuing towards the NW. The only resident raptor seen was an adult Northern Goshawk. Other birds were 2 male Common Goldeneyes, 1 Northern Flicker, 1 Pileated Woodpecker, 3 Grey Jays, 64 Common Ravens (29 of which soared above Mount Lorette at 1700), 1 American Dipper and 1 Grey-crowned Rosy Finch. An American Elk was heard bugling south of the site at 1000, and a season-high 45 visitors were lured out by the sunny weather.

Saturday, March 10 Beaver Mines [Day 14] 0730-1830 (Peter Sherrington). The temperature was -2C at 0730, reached a high of 5C at 1200-1600 and was 2C at 1830. Winds were W-NW10-25 km/h to 1500 after which they were light S-SE and calm after 1800. It was essentially cloudless all day although trace to 20% thin stratus briefly developed from time to time. The first migrant was an adult Golden Eagle at 0811 which is the earliest so far this season, but movement was slow and sporadic with a disappointing total of only 19 raptors moving up to 1640. The count was 6 adult Bald Eagles, 2 light morph Rough-legged Hawks that flew north together at 1604 and 11 Golden Eagles (10a, 1sa). For the first time this season the ridges and mountains to the SW were completely clear and most of the birds seen at Mount Lorette today must have passed to the west of the site. Despite the low count a whole day of warm sunny weather was greatly appreciated.

11 hours (125) BAEA 6 (56), RLHA 2 (9), GOEA 11 (85) TOTAL 19 (154)

Saturday, March 10 Steeples [Day 7] 1100-1815 (Vance Mattson). The temperature was 0C at 1100, rose to a high of 8C and was 2C at 1815. It was calm or light SE winds, and an initial cloud cover of 30% cumulus gave way to cloudless skies after 1500. A season-high total of 68 eagles were counted between 1120 and 1809 that comprised season-high counts of 16 Bald Eagles (9a, 1sa, 6j) and 52 Golden Eagles (49a, 1sa, 2j). The first two migrants were both adult Golden Eagles, at 1120 and 1142, and the next hour saw 13 migrants (5 Bald Eagles and 8 Golden Eagles). The most concentrated movement occurred between 1300 and 1400 with 27 migrants, and the next two hours saw 9 and 10 migrants respectively. No migrants moved between 1600 and 1700, but the pace again picked up slightly with 7 migrants between 1700 and 1815, including the last, a juvenile Bald Eagle, at 1809. Non-migrants were also all eagles consisting of 9 sightings of Bald Eagles (6a, 3j), including a courtship flight of two adults that soared in unison at close proximity, and 3 sightings of resident Golden Eagles. This peak of migrant eagles is comparable to similar numbers in the last two years: 63 migrants on March 11 in 2016, and 94 migrants on March 12 in 2017.

About RMERF

Since 1992, Rocky Mountain Eagle Research Foundation (RMERF) volunteers have performed annual raptor migration counts at the same site location in the Kananaskis Country, Alberta, spring and fall; significantly providing data to the understanding of and amazement in watching Golden Eagles.